Trampolins



R. M. FENNER Erm. l Y 2,799,867

July 23, 1957 Y "rRAMPoLINs 'Y Fle July 26,` 1954 2 Sheets-Sheet l WIX 'ATTORNEY July 23, 1957 R. M. FENNER ETAL.

TRAMPOLINS '2 Sheets-Sheet 2 Filed July 26, 1954 ATTORNEY United Statesif' .217.955.867 Y "mAMroLINS neuve. con.

Thisinvention relates-to a ,bonning acrobatic `[table of the typeknownas a trampoln, andhasator itsprincipal object the provision ofatrampolin-which canbe gnickly and easily folded and mounted fortransportationtbrough resttiotedpaces. Suctls dPOfWaysnQ-.ihe likeAnother object. is to so Vnmstrucf the. :trenitalia that the supportingleg lstructures-will act aswdiagonal brace `structures so'that alltransverse membersbelow thebed or webbing which might beinjurions can beeliminated.

vA further object is to provide Va trampoln in whicljrthe supportinglegs will automatically Afold against thetrampolin sections when thelatter are folded. together, andto provide portable wheeled supports forVtransportingthe trampolin, and,v protective aprons for concealingandpreventing accidental contacts with-the ,trampolinsprings.

Other `objects and advantages reside in, th e` detailrconstruction ofthe invention, which is `designed for simplicity, economy, andeniciency. These will become morey apparent lfrom the followingdescription. a

In the following detailed description `ofthe invention, reference ishadIto `the accompanying drawing. .which forms a part hereof. Like numeralsreferto like parts in all views of thedrawingandthronghout thedescription.

In the drawing:

Eig. lis a plan Vview ofrtheimproved .trampolimrpartially broken away toillustrate the supportingI structure;

Fig. 2 is a side-view thereof in .the erected position;

Fig. 3 is.anvenlarged, dfragmentary, diagonal view, looking along Vthearrow 3 vin-Fig. 1; Y

.Fig- 4 is asimilar enlarged fragmentary Yiiwrlsokng along thearrow 4 inFig. 1;

VFg- 5 iS-.a detail crossfsection through .tbefsaofthe trampoln bed,taken on the line 5 5, Eig.; `l;

, Fig. 6 is a'simiiar detailsec'tion, taken on .the line Y.6v-.6, Fig. lshowing a detail viewi'o'f at protective apron-supporting structureemployed npon, the ,improved trampoln;

Y Fig. 7 is-an.enlarged,-fragrnentary, sfide viewillustrting a type-ofhinge employed in the `improved trampoln;

Fig. 8 is a similarly enlarged, .detailzsectiom taken on the line 8-8,Fig. 7; i

Fig. 9 is a detail, perspective viewon the scale. of Fig. 1,illustratingl a wheeled standard employed for .transporting the improvedtrampolin;

Fig. 10 is aside View ofthe vimproved trampolinas itwouldkappear'whilefbeing folded fortranportationgand Fig. l1 is an endview of theimproved trampohninthe folded, transportation position. l u

The table portions of modern trampolins are-formed from a plurality oflongitudinally 4and laterally/.extending webbingsstitched together toform a llexiblebedbottom, .which will be herein `designated as theffbed."-.Oo .ther types are formed with a single sheetV of ilexible.canvas or the like.

' This improved trampoln isdesigned for use with* either type of bed,and `for convenience of illustration, is'I illustrated as asinglestlexible sheet which willbehereindesignated as thepbed 12. Theexible bedw12 is resiliently supported in a taut, stretched condition bymeans of a atent 2,799,867 Paten-ted Jair ,23. 1957 ice plurality. ofperipheral tension lsprings 13 extending to a supporting framework. Itis in the supporting framework thatthe principal advantages ofv thisinvention reside.

The framework of this improved trampoln comprises two tubular, U-shapedend members 14 and twofstraight, tubular side members 15. The sidemembers 15 extend between `the terminals ofthe two U-shaped end members141m form a rectangular, elongated enclosing frame with four ronndedcorners.

i vThe side members 15 are joined to the extremities of the U-shaped endmembers 14 by means of elongated, channel-shaped hinge members 16, theextremities of which extend on opposite sides of the adjacentextremities of the frame members 14 and 15 and are hingedly secured tothe V,latter by means ofA spaced-apart hinge rivets or pins 17. Thehinge members 16 extend across theptops yofthe joints between themembers 14 and 15 andthe tops ofthe lhinge members are notched back, asindicated at 18, Vtoi provide space to `allow the frame members 1.4 and15 to swing into parallel relation, such as indicatedyin ,broken line atA in Fig. 10. Y U The tension springs 13 aresecured attheir inner. ex-,trernitiesin any desired mannertothe liexible bed 12. They are hookedat their outer extremities through perforatedattachment ribs 19 whichare weldedor otherwise .secured` to, or formed on, t'heinside faces ofthe straight portions of the frame members 14/ and 1S. 'Y

Each of the straight side members`1'5 istrussed against vertical;stresses by means of artruss rod 2llfwhichiswelded to the extremities ofeach'mernben15V aLitsextremieS, and which is rnedially spaced fromthemember. 1.5 by means of a horizontal tubular axle sleeve 21.

The transverse portions of each of the ltlv-shaped frame membersrll isstrengthened and stifened against horizontalstressesby means of a trussmember 22 welded atits extremities to the member 14 and spaced mediallytherefrom by means Vof a suitable spacer 22. j

TheV supporting frame is supported upon f our diagonally positioned,-V-shaped, leg frames 23. "-Eachleg' frame vc nnprises atubular, trussedframe having a rounded bot- 7tornportion,coveredv by. means Vof acushion sleeve 24 of rnbberizedfabric or lother suitable fmaterial 4'to`prevent slippage upon and damage to a floor. The upper extremities ofeach V-.shaped leg frame extend horizontally and oppositelyvoutward toform hinge stubs 25. The hinge vstubs 25 arerotatably receivedl in hingecollars 26, there being oneshinge collar 26 weldedbeneath each extremityof Veach of theU-.shaped frames 14, and twohinge sleeves welded inspaced` relation beneath ,the mid-portion Vof each of the 'yu-shapedframes 14 in aligned pairs so that the ,leg frames will extenddiagonally across the corners of the'Ufshaped frames 14 approximatelybelow the corners of the flexible Abed 12.

The leg frames are prevented from. swingingyoutwardly Aby `means kofvilexible chains 27 extending from the. truss rords 20 at each side tothe leg frames'23.

The leg frames are preventedffromswinging inwardly by means of tubulardiagonal braces 28. Each ,brace has an angularly turned, horizontalupper end portion 29 adaptedV to .be received in a receiving sleeve 3l)Vwelded beneath the Aarcuate Ycorner `of Vthe U-shaped lframeplt. Eachdiagonal brace 12S is also provided withan angularly turned, horizontal,`lower end portion 31 which is rotatably received in a bearing tnbe 32welded yor otherwise secured to the leg frame l23. Each diagonal braceis resiliently held in position in its sleeve 30 and in its bearing,tube 32 ,bymeans of a tensiongspring v33 tensioned between the braceA28 and the leg frame 273.l

It can be seen that if a` weight of other impact isimpoesd upon themedial portion ofr the. llexible bed V12, it will I,tend to pull the twoside frame membersolS inwardly toward each other. VIn the nsual trampolnthis inward pull is resisted by cross-members below the bed which limitthe depressionv of the latter and which are dangerous to users of thetrampoln.

In this improved trampoln, vthis inward pull of the side members istransmitted to the ends of the `Atwo U- shaped frame members, tending topull the latter inwardly. The inward pull on the extremities of theU-shaped frame members s resisted iirst by. the natural Vresistance ofthe members themselves', andV second by the diagonal placement of theleg frames 23, which serve as rigid diagonal braces for the extremitiesof the U-shaped frame members, Vand which act'to transmit the inwardmoment to Vthe mid-portion of each end frame member. rIr'he latter arepreventedfrom bending under the resulting stress by the truss member 22.

lTwoY of the wheeled standards, Aas illustrated in Fig. 9, are employedfor transporting the trampoln. Each of the wheeledstandards comprises ahorizontal base tube 34 supported at its extremities upon caster wheels35. A vertical post or standard 36 is secured to and arises from eachbase tube 34. The upper extremity of each post or standard terminates ina horizontally projecting bearing stud 37. A hooked arm 38 projects fromone side of the upper portion of each post or standard 36, and aU-shaped receiving yoke 39 projects from the other side of the lowerportion thereof. f

Let usrassume that it is desired to fold the trampoln from the erectedposition of Figs. l and 2 and transport it to a new location. The sidesof the trampoln are alternately, slightly lifted and the bearing studs37 of the posts or standards 36 are slipped into the bearing sleeves 21kof the side frame members. The height of the posts or standards 36 issuch that when the studs 37 are Aslipped into the sleeves 21, the bedwill be elevated above its working position.

The end portions 29 of the diagonal braces 28 are pulled from thereceiving sleeves 30 against the action of the springs 33 to release theleg frames. The U-shaped end This is avoided in the improved trampoln byproviding exible aprons 40 along the two sides and the two ends of thebed 12. These aprons are supported above the springs 13 upon resilientsupporting rods 41, the outer extremities of which are turned verticallydownward and inserted through openings in the frame members 14 and 15.The outer edges of the aprons are tied tothe frame members by suitabletying tapes 42. The innerV edges are supported on the inner extremitiesof the rods 41 and are tensioned longitudinally by means of end springs43. This supports the aprons above the springs 13 so that they do notslap and vibrate against the springs. The aprons however, are sucientlyresilient to prevent injury to a body falling thereon, and aresuiiiciently tensioned to prevent the arms or legs ofthe user from beingforced between the springs. Since these aprons are completely tiexble,they fold with the folding of the bed.

While a specific form of the improvement has been Y described andillustrated herein, it is toY be understood frame 14 at the right slifted upwardly, as indicated in solid line at-B in Fig. 10. As itlmoves upwardly, it will increase the tension in the two chains 27 atthat extremity. As the tension increases, the chains will act .to pullthe two leg frames 23 into tight, parallel, folded position on the endmember 14. The folding is continued until. the end member 14, and itsassociated leg frames lie in the folded position as indicated at A nFig. l0. Y' v The U-shaped end member 14 at the left extremity is :nowsimilarly folded upwardlyand folded over'the top "of the folded rightendY frame so that the two end frames and, their associatedleg frameswill lie in horizontal, parallel relation uponthe side frame members 15,supported on the posts 36. The folded structure is now tiltedjtotherrght to a'rvertical position about the axes of the sleeves 21 sothat the side frame structureswill enter into the U-shaped yokes 39 toprevent withdrawal of the bearing studs 37 and to support the entiretrampolin in a vertical position between the posts or standards 36 withthe weightv being carried uponV the four caster wheels 35. Y Thedown-folded'left end frame depends from its ,hinge member over theyup-folded iight end frame to prevent the Ylatter from unfolding. Theheight of the folded structure is onlyV slightly in excess of the lengthVof the side members 15 andthe width is exceed- Aingly narrow so that itcan be conveniently wheeled through doorways and other restrictedspaces.

f When it s desired to unfold the trampoln for use, the folded structures swung upwardly until it strikes therhook arms 33, which4 serve asa'stop. The left end frame is then unfolded, while the hook arms preventthe remainder from tilting'. The right end frame is then unfolded, the

diagonal braces are engaged, andthe posts or standards .36 are removed.The trampoln s now ready for use.

Accidents occasionally occur on trampoln due to the legs and arms Vofthe users dropping betweenY the springs.

that the same may be varied, within the scope of the appended claims,without departing from the spirit of the invention. f

Having thus described the invention, what is claimed and desired securedby Letters Patent is: v

l. A trampoln comprising: an elongated, exible bed; a side frame memberextending along the medial portion of each side of said bed; a U-shapedframe member extending across each end of said bed to the cornersthereofthence extending inwardly from said corners along the opposite sides ofthe extremities of said bed toward said side frame members; an elongatedhinge link connecting each extremity of each U-shaped framemember to theadjacent extremity of one of said side frame members; tension springssecured to and extending between said bed and said frame members; fourV-shaped leg frames, there being one of said V-shaped leg framesVpositioned below and extending diagonally across each corner of eachU-shaped frame member; hinge means securing the extremities of each ofsaid V-shaped frames to the adjacent U-shaped frame member, and flexibletension members, each secured at one end to an intermediate point of anadjacent side frame member `and at the other-end to said leg frame toretain said leg frames from spreading when` set up. f Y

2. A trampoln as described in claiml l in which Vthe hinge means at `oneextremity of each V-shaped leg memher s positioned adjacent theextremity of one of said U-shaped frame members `and the hinge means atthe Y of'a U-shaped frame member.

3. A trampoln as described in claim 2 having a truss member mounted onthe mid-portion 'of'each U-shaped frame member resisting flexure of thelatter in the plane of said bed; and an additional truss memberv mountedon each of said straight portions of said'sde frame members resistingvertical flexure thereof. n

4. A trampoln as described in claim 3 having a bearing sleeve mounted at`the .middle of'y each side frame member in axial alignment with eachother; two supporting posts; a stud projecting from Veach post, saidstuds adapted to be received in said bearing sleeves to rotatablysupport said frame members and said bed; and wheels supporting eachpost.

5. A trampoln comprising: an elongated, exible bed; Va side frame memberextending along the medial portion of each sdverof said bed; a U-shapedframe member extending across each end of said bed to the cornersthereof thence extending inwardly from said cornersV along the oppositesides of the extremities of said bed toward said side frame members; anelongated hinge link connecting each extremity of each U-shaped framemember to the tension springs secured to and extending between said bedand said frame members; leg frames supporting said U-shaped framemembers; a bearing sleeve secured at the middle of each side framemember, said sleeves being in horizontal aXial alignment; a pair ofsupporting standards; Wheels supporting each standard; and la pivot studprojecting from each standard, said studs being adapted for insertion insaid sleeves to rotatably support said frame members and said bed in atilting position.

6. A trampoln as described in claim 5 having an arm member projectingfrom each standard and acting to prevent tilting of said frame membersand bed in one direction; and a yoke device mounted on each standardadapted to receive said frame members when the latter are tilted in theopposite direction to prevent withdrawal of said pivot studs from saidbearing sleeves.

References Cited in the le of this patent UNITED STATES PATENTS 411,687Seibert Sept. 24, 1889 1,347,413 Schaefer July 20, 1920 1,722,413Ellsworth July 30, 1929 2,370,990 Nissen Mar. 6, 1945 2,513,168 GottliebJune 27, 1950 FOREIGN PATENTS 209,293 Switzerland 1940

